Wobble plate engine



July 29, 1947. F. c, HOWARD WOBBLE PLATE ENGINE Filed 'llay 7, 1945 ,2Sheets-Sheet l INVEN TOR. Cf MHz/d BY /bagfl WH 7H July 29, 1947. F. c.HOWARD 2,424,660

WOBBLE PLATE ENGINE Filed May 7, 1945 2 Sheets-Sheet 2 met withpractical success.

aienied July 29, 1947 wonntn PLATEENGINE Y Frank 0. Howard, Ilearborn,Mien. v Application May '1, 1945, Serlal No, 592,346 2o omms. (01314-40)The present invention relates to a wobble plate engine of the typeemploying a circular ring of stationary parallel cylinders, a drivenshaft concentric with and parallel to the cylinders, a wobble platelournaled on the shaft about an axis inclined to the shaft, and pistonsin the cylinders operatively connected to the .wobble plate at fixedpoints around its circumference. 7

It has long been recognized that, in theory, an

' engine of the above type has many advantages over crank type engines,but in spite of many prior efiorts to design such an engine, nonehaveknown for many years that the primary defect in prior designs lay in themechanism for controlling the motion of the wobble plate about itsinclined axis. This mechanism must so connect the wobble plate to astationary portion of the englue that any point on the wobble plate willtrace a spherical lemniscate during each revolution of the shaft; and itmust be suficiently rugged to sustain the entire torque reaction of theengine. The recognition of the failure to solve this problem has ledworkers in the field to attempt to avoid it by employing designs whichdo not impose the torque reaction on the. wobble plate (S. A. E. Journal,.Transactions, vol 47, No. 6, December 1940; and U. S. Patent No.2,303,838). These have greatly complicated the engine and have notproved practical.

Accordingly, it is the object of the present invention to provide awobble plate engine of the type mentioned which incorporates anexceedingly simple, compact, and practicalmeans to prevent rotation ofthe wobble plate about its own axis and to sustain the torque reactionof the en- 'gine.

Another object of the present invention is to providemechanism of thetype mentioned in combination with a wobble plate shaft coaxial with thecylinder block and iournaled at both sides of the wobble plate.

Another object of the invention is to provide an improved type of wobbleplate and mounting therefor.

Other objects and advantages of the invention will become apparent fromthe following specification, the accompanying drawings, and the appendedclaims.

In the drawings, I

Figure l is a longitudinal sectional view of a preferred form of theinvention;

Figure 2 is a fragmentary view of a portion of the mechanism, partiallyin section, on the line 2-2 of Figure l;

the line 3-3 of Figure: 1.

Figure is a sectional view taken generally on Figure 4 is anelevation-view 4-4, of Figurev 3. a v

The drawings illustrate only those portions of an internal combustionengine to which the invention taken on the line ral'ates, and,consequently, do not show the cylinder-head orv valve mechanism, etc.,but simply It has also been the cylinder block,-the pistohs, and themechanism by means of which the pistons actuate the engine shaft. Thus,in Figure 1, is shown an illustrative form .of the engine comprising acylinder block l which constitutes a' stationary portion of the engineand which is provided with a plurality of cylinder bores 2. While onlytwo of the cylinder bores appear in Figure l,lt is to be understood thatany desired number of cylinder bores may be providedso long as they arearranged parallel to and in a circle about the axis 3 of the'engineshaft 4, which is the driven element of the engine. The particularengine illustrated has seven equally spaced cylinder bores of the samediameter. The enlarged right-hand end 5 of theengineshaft 5 is:lournaled within an end closure plate 6 by means of a ball bearingassembly, indicated generally at 1. While any desired form of combinedradial and axial thrust shaft by means of the flywheel H and a spacingsleeve i2, the flywheel being secured to the end of the shaft by aplurality of cap screws i3. The outer races 9a and 9b are clampedagainst the end closure plate 6 by means of a clamping ring l4, which issecured in position by means of a plurality of cap screws iii. The races9, 9a, and 9b are so formed that. each of the balls 8 makes atheoretical point contact with each of the races 9a. and So at twospaced point contacts with the inner race 9. Consequently, the bearingwill support the shaft against the end thrust as well as radial loads.The endclosure' plate 6 is fixed to the cylinder block I by means of abarrel it.

The left-hand end of the engine shaftil has a reduced portion i! whichis journaled by means of a cylindricalneedle bearing l8 within a sleeveI9. The sleeve i9 is slidably supported on aring 2D fitted'within acircular opening -2"! formed in the cylinder block coaxial with the axisof the shaft. The left-hand end of the sleeve is providedwith a splinedsection 22 having a sliding V 3 v spline connection with a ring 23 whichis fixed in any suitable manner to the cylinder block.

A generally circular disk 24 having a cylindrical flange 25 is formedintegrally with, or other:

wise fixedly secured to, the "shaft 4 in such manner that the" axis 26of the cylindrical flange 25""v extends at an'angle to and intersectsthe axis 3- the shaft 4 at the pointjndicetted by the'nupoint 21 ofintersection between the axes 3 and 26. An annular wobble plate 28 isJournaled by means of a ball bearing assembly, identical in constructionand mode of operation to the pre-' viously mentioned bearing 3|, uponthe cylindri-- cal flange 25. The inner race 30 of the bearing 26 isclamped against the disk 24 by means of a -nut'3l which is threaded uponthe extremity of the flange 25. The outer races 32 and 33 are clampedagainstian internal shoulder 34 formed in the wobbleilplate 28by meansof a clamping nut '35. As a result of this arrangement the wobble plate28 isfree to rotate with reference to -thecylindrical flange 25 onthesshaft 4 and thus a "remain stationary while shaft 4 rotates.

Theleft-hand face of the wobble plate 28, as viewed in Figure 1, isprovided with a plurality or circular recesses 36, each having its axisextending parallel to the axis 26.- One such recess is provided for eachcylinder 2 in the cylinder block. In each recess 36 is fitted acylindrical block 31 having a semispherical concave recess 38 adapted toreceive the sphericalend 39 formed on a, threadedstem 40. The sphericalend 39 is retained against displacementfrom the recess 38 -bv means ofan annular cap 39 provided with an internal concave surfaceof annularconfiguration, the retaining cap 38 being secured by means of cap screws4| to the left-hand tace ot the wobbleplate 28.

1 intersection between the axes 3 an d 26.

radial distance from the point 2 l,to the center varied by substitutingwashers ofdiflerent thicknesses in placegithe-wflher 5|. f

From the above it will be apparent that, an operative connection isprovided between each piston anda fixed point on the wobble plate 28,such point being locai'ed'at the'cen'ter or'the spherical ball 39. Itwill be furthei noted that the point of connection, namely, thecenter ofball 36, is locatedin the plane which is Formal to the axis 26 andpasses through the point 21f of The of each-ball 39 is such that whenthe ball 39 "is in the midpoint of its. strokai): will be located at thesame distance above the a of the cylinder 2 of B18142}? inder 2 when asit lies below the axis it is at either end of Itsstrcke.

An important feature of the wobble plate con struction so far describedresides in the fact that the bearing 29, which supports the wobbleplate,

is located at substantially the same distance from the axis 3 of theshalt 4 as are the axes of the of a tubular connecting rod 42,theopposite end of which is fixed in any suitablemanner, as by welding, toa sleeve 43 by means of which the connecting rod is secured to thepiston pin 44' of a piston 45, in such manner as to permit limiteduniversal movement of the connecting rod with reference to thepisto'npin. This connection iselfective by means of a sleeve 46 havingan internal cylindrical opening journaled upon the pin 44 and having anexternal spherical surface 41 journaled within a corresponding sphericalinternal surface formed in a sleeve 48 which is fixed within the sleeve43. The sleeve 48 is split in the plane of the dotted line 49 of Figure1 so that it maybe removed from the sleeve 46.,

A pin 50, indicated in dotted lines in Figure 1, is fixed to the sleeve43 and is journaled within suitcylinders 2. As a matter oifa'ct, thediameter-oi the bearing is so chosen that that portion of the bearingwhich, at any given instance, is closest v to the cylinder block islocated substantially on the axis of the adjacent cylinder and is,therefore, in aposition to sustain the direct in-line thrust of thepiston at the time of explosion. This relieves the wobble plate bearingof all load multiplication, due to an application of the load to thewobble plate at a point spaced radially outwardly of the bearing at thetime of explosion.

It is well known that, with a connectionbetween the pistons and thewobbleplate which is located in fixed position circumierentially withrespect to the wobble plate, the to'rces applied to the wobble plate bythe 'pistonswill tend not only to rotate the shaft 4 but also to,-rotate the wobble plate 36 with respect to the axis of the cylinderblock l. Accordingly, it is essential in all engine constructions ofthis type to employ means to prevent rotation of the wobble plate. Suchmeans must absorb the entire torque reaction 01 the engine and,consequently, is subject to exceedingly heavy loads of constantlyvarying intensity. Moreover, as is well known, to avoid destructivevibration at ordinary engine speeds, it is essenable openings formed inthe sleeves 46 and 48 in 7 nccting rod 42 and the sleeves 4' 3 and 46about the axis of the pin 50, which axis is at right angles to the axisof the piston pin 44. The connecting rod 421's permitted to oscillateabout the axis of piston pin 44 by reason of relative movement betweenthe sleeve 45 and the piston pin. It will be noted that a spacing washer5| is provided between a shoulder on the member 40 and the right-handend of the tubular connecting rod 42. The compression ratio of theengine may be tial to so restrain the wobble plate against rotation asto insure that each point on the wobble plate in the plane containingthe centers of balls 39 travels in a curved path which is known as aspherical lemniscate, i. e., a figure 8 drawn on the surface, of asphere. This essential motion for the centers of the balls 39 isindicated in dotted lines in Figure 1. Thus, the lernnlscate, as viewedfrom the side in Figure 1, appears as an arcuate line indicated by thedotted line 52. When viewed from above, the curve appears as a figure 8,as indicated in the dotted line 53 above Figure 2. When viewed from theend, the curve appears as a small circle, indicated at the right ofFigure 1 by the numeral 54.

It has been known that it it were possible to connect the wobble plateto the cylinder block 01' the engine by means of a constant velocityuniversal joint, the wobble plate would be given the type of restraintrequired to produce the above described movement of the centers of theballs 35, but no one has succeeded in so restraining the available whichwould be effective under the 1 heavy loads and at the relatively highangle required.- Moreover, prior attempts to incorporate a constantvelocity joint connection betweenthe wobble plate and the cylinderbarrelhave involved anattempt to locate the torquetransmitting eleuniversaljoint comprises a ring 55 surrounding the shaftll and-provided with twopairs of aligned radially extending trunnions 58 and" 51. The

trunnions 58 are aligned with each other and extend at right angles tothe-aligned trunnions 51,

the point of intersection of the two pairs of trunnions lying on theaxis 3 of the shaft 4. The

loads would have to be of substantial size, and it a is essential'in awobble plate engine to maintain the wobble'plate at the smallestpossible diameter.

sothat foriafEiven pistqnstrokethe angle of the wobble plate axis to theshaft axis may be as large as possible. Moreover, it is highly desirableto/provide supporting bearings for the engine shaft on both sides of thewobble plate. Consequently,'the shaft extensions materially reduce theamount of space available for use of any type of universal joint; Asingle Hooke's or ordinary trunnion universal joint will not provide theproper wobble plate. restraint and will set up a destructive vibrationat a frequency which is twice engine speed. The use of two ordinaryuniversal joints so connected as to transmit con-' stant velocity hasbeen successful in pumps in which the piston operating disk is directlydriven about its own axis and the cylinder barrel is likewise drivenabout an inclined axis. However, in such constructions no torquereactionor driving load is sustained by the universal joints, andthere is noelement corresponding to the engine shaft in a wobble plate engine whichmust pass through the same space occupied by theuniversal joints. Theuse of two universal joints so connected as to V transmit constantvelocity has also been suggested in pumps of the typeemploying tiltingboxes to. support the piston operating disk in a given plane. In suchconstructions the cylinder block is rotated by the shaft and the disk isconnected by .the two'joints to the shaft. In such I constructions,however, the problem is not critical because the shaft does, not sustainany bending loads as the result of piston thrust, and con-' sequentlymay be cut away to make room for one or" both joints. Moreover, theoperating requirements and conditions of. hydraulic pumps and motors aremuch less severe than internal combustion engines. In accordance withthe preferred embodiment of the present invention the necessaryrestraint of thewobble plate is provided by a pair of fourtrunnionuniversal joints located within the radius of the wobble plateandarranged to transmit a constant velocity if either were rotated.Actually, however, since neither joint is" rotated they maintain thewobble plate against rotation about its own axis. These jointsare'specially constructed and arranged to sustain the heavy torquereaction incident to operation of the englue, and at the same time tooccupy so little space as to require no enlargement of the circle inwhich the-axes of the cylinder bores. lie.-

that they do not interfere with an extension of the drive shaft on bothsides ofthe wobble plate and thus permit a joumal support for the shaftat both ends. 1

Referring to the drawings, it will be noted thatthe shaft 5 is somewhatreduced in diameter at "ternal bore in the spherical bearing members 60.

T similar to the ring 65, and the ring is provided the point 21 ofintersection between those axes.

pair of axially projecting parallel arms 13 located "is provided with acylindrical recess 14, similar .60

Furthermore, these joints are so constructed .65

utremities of the projections 13 are provided with the left-hand side ofthe disk 24 and makes a/- more or less gentle curve .inthe region of theintersection. of the axes 8 and 25. The first which aregenerally-cylindrical with their axes 59 by means'of capscrews 82, thepositions of a which are indicated in dotted lines in Figure 3.

two radially inwardly projectin g'arins 88, the

.by the projections 69, that the centersof the joint by the means bestshown in Figures 2, 3,

and 4, retains the spherical bearing member 15 respectively with therecesses 14. The spherical fbearing members 19 fitted within therecesses 18 I contain needle rollers 88 which rotatably supporttrunnions 56 are connected to. the aforementionedsleeve l9 byself-aligningbearings. Thus, the sleeve 18 is provided with a pair ofprojecting arms 58 provided at their ends with recesses 59- extendingparallei to theaxis 3 and which have conically shapedbottom walls. Aspherical bear ing member 581s fit-ted within each recess 58 and is heldin position by a retaining cap 8|, which is secured in position oneither side of the recess Antifriction needle rollers 63 are providedbetween the trunnions 58 and the walls of the in- The second universaljoint comprises a ring 84 with two pairs of aligned trunnions "65 and58. Thetrunnions 65are similarly journaled by antifriction needlerollers in spherical bearing members 61; The wobble plate 28 .isprovided-with inner extremities of whichlie on opposite sides of theaxis 26 and have axial projections 89 which extend, to the right, asviewed in Figure 1, into the space within-the cylindrical flange 25. Theprojections 69 are provided with cylindrical openings 10 whose axesextend parallel to the axis 26 and which are similar to the recesses 59in arms 58 except that their'open ends are to the left. The open ends ofthe recesses 18 are closed. and the spherical bearing member-81 held inposition in the recesses by means of a pair of retaining caps 1| similartothe caps Si in the left-hand universal joint.

Thealigned trunnions 56 are so held by the arms 58, and thealignedtrunnions 65 are so held two 'joints liein the axes 3 and 26,respectively, at equal distances from and onoppositesides of In order tocomplete the torque transmitting connection between the two-joints, thealigned trunnions 51 of the left-hand joint are connected to the alignedtrunnions 66 of the right-hand and 4. The connecting member is ,in theform of a ring, indicated generally at 12, which has a on opposite sidesof theshaft 4. The left-hand face of the ring in the vicinity of eachprojection to the recsses59 and 18, which recess is. adapted to receivea'spherical bearing member 15 containing .a pluralityof antifrictionneedle rollers 16 andconstituting bearings for the trunnions 51. Aretaining cap 11, shown best in Figures 3 in the recess and areidentical insconstruction to the aforementioned bearing' caps 8|. Theexsimilancylindrical recesses 18 which are aligned the trunnions .65 ofthe right-hand joint. Retaining caps 8| retain the'spherical bearingmem-; ber 18 within the recesses 18. As a result of-this joints;

,tweenthe joints and surrounding the shaft 4, is

' arrangementthe aligned trunnions SI'are always held parallel to thetrunnions 58 by the ,ring- 12.

It will be observed that in gccordancewith the above describedconstructionthe two connected universal joints areso arranged that theywill a which will be imposed upon thetrunnions and the rings 55, 54, andI2, the joints and their conabsorb the entire torque reactionof theengine v and s restrain the movement of the wobble plate 28 that thepointer connection between the wob-' ble plate aridponnecting rod willtravel in the path of the spherical lemniscate indicated by dotted linesin Figure l, as is required toaeliminate destructive vibration; The, twouniversal necting ring 'l2 will .be subject to deformations underload'beyond those ordinarily encountered in universal joint practicefiSuch deformations, however, are fully accommodated by the'selfaligningspherical bearing members which may have a, limited rotation withintheir recesses in response'to any distortion which results under heavyloading, "and thus remain in a position in- "whichtheir central openingsare parallel to the joints are ,soconstructed thatthey surround thedrive shaft 4 andare'iree ofcontact therewith. Consequently,-they permitthe use of the outboard bearing i8 for- :theshaft and thus permitjourco-operating trunnion. This insures that the full load capacity ofthe bearing will be available at "all times. 7

The reviously described sliding connection be- I tweenthe sleevei9,-which carries theuniversal naling of the shaftia't both sides ofthewobble plate. This greatly strengthens the lwobble plate constructionand reduces distortion-of the. drive --shaft as well as the loads-uponthe drive shaft bearing.1g l,

Moreover, it will be noted that the construction of the universaljointsand theconnection between them is, so arranged as to permit the use of awobble plate oi minimum diameter. In that connection it, should bementioned that the enwould not be possible to have seven cylinders ofequal size arranged with parallel axes in a circle about axis 3, ifthediameter ofthatcircle were any less than the distance betweentheaxesof the cylinder bores 2, illustrated in Figure l, without resultingininsufilcient -wallthickness bemuni diameter for a seven cylinder enginehaving pistonsof the diameter illustrated. The wobble plate is alsoclosely coupled to the pistons. Nevertheless, the universal joints andthe connection between them are so constructed that they-will notinterierewith any of the other mechanism. This is achievedin part' bythe peculiar construction of the ring 12 which'forms the connectingmember between the, universal This ring, instead of being'locatedbelocated generally in the plane of a left-hand joint and is providedwith generally arcuate portions 82 whichsurroundthe projectingarms 58 onthe sleeve 19 and which connect the portions of the ring adjacent theprojections I3. The cross-sectional form of the arcuate portions, asbest shown in the upper part of Figure 1, is such that they will justclear the cylinder-block i, the projecting arms 58, and the wobble-plate28, includjoint arms 58, and thecylinderblock further operates toprevent excessive loading on the universal joint trunnion bearings whichmight other- 2of wise result from distortion of the shaft 4 or the frameof the engineer unequalexpansion of various partsof the engine due tothe heat of the operation, since 'it permits a limited axial sliding ofthe left-hand universal joint along the axis 3 and thuseliminates'endwise tension or compression forces on the universal jointassembly.

gineillustrated is a seven cylinder engine, andit The needle bearing i8between the shaft 4 and the sleeve 19 permits limited relative sliding Ymovement between the shaft'and the sleeve for tween the respectivecylinder bores of the cylinder block. Thus the engine illustrated is ofmlni'- -v the same purpose.

The trunnion bearing may be lubricated in any desired manner as bysplash or oil feeding systems, not shown, which will supply oil toopenin'gs. 83 formedthrough each'trunnion and the ring, of whichit formsapart. Alternatively, if

desired, the antifriction'needle bearings may be filled with grease onassembly and a seal provided between the .open end of each sphericalbearing member and the base of the'trunnion with which it is associated.V

The engine maybe substantially balanced against the inertiaefiects'ofthe wobble plat by "means of a counterweight 84', secured inthe position illustrated in Figure l, to the flywheel l l.

'While only one form of the invention is illustrated and described itwill be apparent that variations in the design of construction may beindulged in without departing from the spirit of the lnventionor' thescope of the appended claims. Thus, the engine may have any desirednumber of cylinders and may, if desired, be providedwith a second bankof cylinders at the righting its inwardly projecting arm 58 and theretaining ring 39 when the position of thatportion of the wobble plateopposite theannular ring portion 82 isclosest to the cylinder block. The

projections 13 of the ring 12 on the other hand are, as best shown inFigure 3, atv a portion of the ring which is of a reduced diameter and,consequently, the projections 13 may, extendinto the interior of thecylindrical flange 25, intermediate the projectionsBB on the wobbleplate, andfconnect to the trunnions 66 :without interference either withthe cylindrical flange 25 or the shaft 4.

The universal joint trunnlons are of necessity relatively small'in sizeand since they must carry the very heavy torque reaction; while workingat asu-bstantial angle, their hearings will be isubject to very highunit pressures, and it is for that reason that antifriction needlerollers are employed in the trunnion bearings. Moreover, due

to the-lack of space and the resulting high stresses 73 culiarly adaptedfor use in an internal combus- 'tion engine where'high speeds and heavyloads are essential to commercially practical design. It will beappreciated, however, that the mechanism may also be used to advantagein highspeed hydraulic 'pumps and motors.

What is claimed is:

- 1. 5 A wobble plate mechanism comprising a stationary cylinder blockhaving a plurality ofparallel cylinders arranged in a circle, pistons inthe cylinders, a rotary shaft parallel to said cylinders and coaxialwith'said circle, an annular wobble plate journalled-on said shaft on anaxis inclined to and intersecting the shaft axis, means operativelyconnecting the pistons to the wobble plate at points fixedcircumferentially on the-wobble plate, means for'absorbing the torquereaction on the wobble plate and restraining its movement comprising auniversal joint having a member provided with a pair of alignedtrunnions, means plvotally connecting said trunnions to a stationaryportion of the mechanism on an axis perpendicular to the'axis of saidaligned tJJmIIiOHS, a second universal joint having a pair of alignedtrunnions, means plvotally connecting said trunnions of the second jointto the wobble plate on an axis perpendicular to the axis of'said secondpair of trunnions, the centers of said joints being located respectivelyon the axis of the shafta'nd the axis of the wobble plate on oppositesides of and at equal distances from'the intersection of said axes, andmeans connecting said pairs of trunnions for maintaining them parallelto each other.

2. A wobble plate mechanism comprising a stationary cylinder blockhavinga plurality of parallel cylinders arranged in a circle, pistons in thecylinders, a rotary shaft parallel to said cylinders and coaxial withsaid circle, an annular wobble plate journalled on said shaft on an'axis inclined to and intersecting the shaft axis, means operativelyconnecting the pistons to the wobble plate at points fixedcircumferentially on the wobble plate, means for absorbing the torquereaction on the wobble plate and restraining its movement comprising auniversal'joint having a member provided with a pair of alignedtrunnions, means plvotally connecting said trunnions to a stationaryportion of the mechanism onan axis perpendicular to the axis of saidaligned trunnions, a seconduniversal joint having a pair of alignedtrunnions, means pivotally connecting said trunnions of the second jointto the wobble plate on-an axis perpendicular to the axis of said secondpair of trunnions, the centers of said joints being located respectivelyon the axis of the shaft and the axis of the wobble plate on oppositesides of and at equal distances from the intersection of said axes,means surrounding said shaft and connecting said pairs of trunnions formaintaining them parallel to each other, and bearings for theintersection of said axes, and means connect-' and coaxialwith saidcircle, an-annular wobble plate journaled on said shaft on an axisinclined to and intersecting the shaft axis, means operativelyconnecting the pistons to the wobble plate 1 at points fixedcircumferentially on the wobble said shaft on opposite sides of saiduniversal joints 3. A wobble plate mechanism comprising a stationarycylinder block having a plurality of parallel cylinders arranged inacircle, pistons in the plate, means for absorbing the torque reaction onthe wobble plate and restraining its movement comprising a universaljoint having a member provided with a pair, of aligned trunnions, meansplvotally connecting said trunnions to a stationary portion of themechanism on an axis perpendicular-to the axis of said alignedtrunnions, a second universal joint having a pair of aligned trunnions,means pivotally connecting said trunnionsof the second joint to thewobble plate on an axis perpendicular to the axis ofsaid second pairoftrunnions, aringmember for each joint, each said ring membersurrounding the shaft and connecting the trunnions of its joint, thecenters of said joints being located respectively on the axis of theshaft and the axis of the wobble plate on opposite sides-of and at equaldistances from the intersection of said axes, means surrounding saidshaft and connecting said pairs oftrunnions for maintaining themparallel to each other, and bearings for said shaft on opposite sides ofsaid universal joints. w

5. -A wobble plate mechanism comprising a stationary cylinder blockhaving a plurality of par- "allel cylinders arranged in a circle,pistons in the cylinders, a rotary shaft parallel to said cylinders andcoaxialwith said circle, an annular wobble plate journaled on. saidshaft on an axis inclined to andinterse'cting'the shaft aXis meansoperatively connecting the pistons to the wobble plate at points fixedcircumferentially ,on the wobble plate, means for absorbing. the torquereaction on the wobble plate and restraining its movement comprising auniversal joint having a member provided with a pair of alignedtrunnions, means plvotally connecting said trunnions to a station-- aryportion of the mechanism on an axis,perpendicular to the axis of saidaligned trunnions, a

cylinders, a rotary shaft parallel to saidcylinders and coaxial withsaid circle, an annular wobble plate journaled on said shaft on an axisinclinedto and intersecting the shaft axis, means operatively connectingthe pistons to the wobble plateat points fixed circumferentiallyon thewobble plate, means for absorbing the torque reaction on the wobbleplate and restraining its movement comprising a universal joint having amember provided with a pair of aligned trunnionsQmeans plvotallyconnectingsaid trunnions to a station-' ary portion of the mechanism onan axis perpendicular to the axis of said aligned trunnions, a seconduniversal joint having a pair of aligned trunnions, means plvotallyconnecting said trun nions of the second joint to the wobble plate on anaxis perpendicular to the axis of said second pair of trunnions, a ringmember for each joint, each said ring member surrounding the shaft andconnectingthe trunnions of its, joint, the centers of said joints beinglocated respectively on the axis of the shaft and theaxis of the wobbleplate on opposite sides of and at equal distances from second universaljoint having a pair of aligned trunnions, means plvotally connectingsaid trun+ nions of the second joint to the wobble plate on an i axisperpendicular to the axis of said second pair of trunnions, thecentersof said joints being 10-- cated respectively on the axis of the shaftandthe trunnions and the stationary portion of the en-; ginebeing'adapted'to permit movement'ofthe theshaftaxis of-the wobbleplateon opposite sides of and at equal distances from'the intersectionof said axes, and means connecting said pairs of trunnions formaintaining them parallel'to each other, the connection between saidfirst pair; of

center of the first joint along the axis of relative to the cylinderblock.

6. A wobble plate mechanism comprising a stationary cylinder blockhaving a plurality of parallel cylinders arranged in a circle, pistonsin the cylinders, a rotary shaft parallel to said cylinders andcoaxial'with said circle,anannular wobble plate journaled on said shafton an axis inclinedto and'intersecting the shaft axis, means operativelyconnecting the pistons to the wobble plate at" points] fixedcircumferentially on the wobble platameans for absorbing the torquereaction onthe wobble plate'and restraining its movement comprising auniversal joint having a member provided with a pair of alignedtrunnions, means pivotally connecting said trunnions to a stationaryportion of the mechanism on an axis perpendicular to the axis of saidaligned trunnions, a second universal joint-having a pair of alignedtrunnions, means pivotally connecting said trunnions of the second jointto thewobble plate on an axis perpendicular to the axis of said secondpair of trunnions, the centers of said joints being located respectivelyon the axis of the shaft and the axis of the wobble plate on oppositesides ofand at equal distances from the intersection of said axes, meanssurrounding said shaft and connecting said pairs of -trunnions formaintaining .them parallel to each other, and

a second universal joint having a pairof aligned trunnions, means pivtally connecting said trunnions of the second mango the wobble plate onan axis perpendicular to the axis of said second pair of trunnions, aring member for each joint, each said ring member surrounding the shaftand connecting the trunnions of its joint, the centers of said jointsbeing located respectively on the axis of the shaft and the axis of thewobble plate on opposite sides of and at equal distances from theintersection of said axes, means surrounding said shaft and connectingsaid pairs of trunnions for maintaining them parallel to each other, and

' bearings for said shaft on opposite sides of said bearings for saidshaft on opposite sides of said universal joints, the connection betweensaid first pairof trunnions and the stationary portion of the enginebeing adapted to permit movement of the center of the first joint alongthe axis of th shaft relative to the cylinder block.

7. A wobble plate mechanism comprising a sta-' tionary cylinderblockhaving aplurality of parallel cylinders arranged in a circle, pistons inthe cylinders, a rotary shaft parallel to said cylinders and coaxialwith said circle, an annular wobble plate journaled on said shaft on anaxis inclined to and intersecting the shaft axis, means operativelyconnecting the pistons to the wobble plate at points fixedcircumferentially on the wobble plate, means for absorbing the torquereaction on the wobble plate and restraining" its movement comprisingnauniversal joint having a member provided with a pair of alignedtrunnions, means pivotally connecting said trunnions to a'stationaryportion of the mechanism on an axis perpendicular to the axis of saidaligned trunnions, a second universalajoint'having a pair of alignedtrunnions, means pivotally connecting said trunnions of; the secondjoint to the wobble plate on an axis perpendicular to the axis ,of saidsecond pair of trunnions, a ring member for each joint, each said ringmember surrounding the shaft and connecting the trunnions of its joint,the centers of said joints beinglocated respectivelyon the axis of theshaft and the axis of the wobble plate on opp s te sides of and at equaldistances from the intersection ofjsaid axes, and means connecting saidpairs of trunnions for maintaining them parallel to each other, andbearings for said shaft on opposite sides of said universal joints,

the connection between said first pair of trun-' nions and thestationary portioni'of the engine being adapted to permit movement "ofthe center of the first joint along the axis of the shaft rela- 1 tiveto the cylinder block. a a

A wobble plate mechanism comprising a stationary cylinder block having aplurality of parallel cylinders-arranged in a circle, pistons in thecylinders, a rotary shaft parallel to said cylinders and coaxial withsaid circle, an annular wobble plate 'journaled on said shaft on an axisinclined to and intersecting the shaft axis, means operativelyconnecting the pistons to the wobble plate at points fixedcircumferentially. on the wobble plate, means for absorbing the torquereaction on the wobble plate and restraining its movement comprising auniversal joint having a member provided with a pair of alignedtrunnions, means pivotally connectingsaid trunnions to a stationaryportion of the mechanism on an axisperpendicular to the axis of saidaligned trunnions,

the cylinders, a rotary shaft parallel to saidv cylinders and coaxialwith said circle, an annular wobble plate journaled on said shaft on anaxis inclined to the shaft axis, means operatively connecting thepistons to the wobble plate at points fixed circumferentially on thewobble plate, means for absorbing the torque reaction on the wobbleplate and restraining its movement comprising a four trunnion universaljoint connected to a stationary portion of the mechanism with the centerof the joint on the axis of said shaft, a

second four trunnion universal joint connected to the wobble platewithits center on the axis of the wobble plate, the centers of saidjoints being located on opposite sides of and at equal distances fromthe point of intersection of said axes,

anda member operatively connecting one pair of aligned trunnions of oneof said joints with a parallel pair of aligned trunnions of the otherjoint.

10, A wobble'plate mechanism comprising a stationary cylinder blockhaving a plurality of parallel cylinders arranged in a circle, pistonsin the cylinders, a rotary shaft parallel to said cylinders and coaxialwith said circle, an annular wobble plate journaled on said shaft on anaxis inclined to theshaft axis, means operatively connecting the pistonsto the wobble plate at points fixed circumferentially on the wobbleplate,- means for, absorbing the torque reaction on the wobble plate andrestraining its movement comprising a four trunnion universal jointconnected to a stationary portion of the mechanism with the center. ofthe joint on the axis of said shaft, a second four trunnion universaljoint connected to ,the wobble plate with its center on the axis of thewobble plate, the centers of said joints being located on opposite sidesof and at equal distances from the point of intersection of said axes,bearings for said shaft on opposite sides of said universal joints,a'ring member for each joint surrounding the shaft and connecting thetrunnions of its joint, and a member surrounding the shaft andoperatively connecting one pair of aligned trunnions of one of saidjoints with a parallel pair of aligned trunnions of the other joint.

11. A wobble plate mechanism comprising a stationary cylinder blockhaving a plurality of parallel cylinders arranged in a circle, pistonsin the cylinders, a rotary shaft parallel to said cylinders and coaxialwith said circle, an ana 13 atively connecting the pistons to the wobbleplate at points fixed circumferentially on the wobble ,plate, and meansfor absorbing the torque reaction on the wobble plate and restrainingits movement comprising a four trunnion universal joint connected to astationary portion of the mechanism with the center of the joint on theaxis of said shaft, a second four trunnion universal joint connected tothe wobble plate with its center on the axis of the wobble 'plate, thecenters of said joints being located on opposite sides of and at equaldistances from the point of intersection of said axes, and a member'operatively connecting one pair of aligned trunnions of one of saidjoints with a parallel pair of aligned trunnions of the other joint,said member being in the form of a ring surrounding but not connected tothetother pair of aligned trunnions of the first joint and having a pairof axial projections which provide bearings for the trunnions of thesecond joint.

12. A wobble plate mechanism, comprising a stationary cylinder' blockhaving a plurality of parallel cylinders arranged in a circle, pistonsin the cylinders, a rotary shaft parallel to said cylinders and coaxialwith said circle, an annular wobble plate journaled on said shaft on anaxis inclined to the shaft axis, means operatively connecting thepistons to the wobble plate at points 1 fixed circumferentially on thewobble plate, means universal joints, aring member for eachjointsurrounding the shaft and connecting the trun-- nions ofits joint,and a member surrounding the shaft and operatively connecting one pairof aligned trunnions of one of said joints with a parallel pair ofaligned trunnions of the other joint, said member being in the form of aring surrounding but not connected to the other pair of alignedtrunnions of the first joint and having a pair of axial projectionswhich provide bearings for the trunnions of the second joint.

13. A wobble plate mechanism comprising a stationary cylinderblock-having a plurality of parallel cylinders arranged in a circle,pistons in the cylinders, a rotary shaft parallel to said cylinders andcoaxial with said circle, an annular wobble plate journaled on saidshaft on an axis inclined to the shaft axis, means operativelyconnecting the pistons to thewobble plate at points fixedcircumferentially on the wobble plate, the journal between the wobbleplate and the shaft being a combined radial and axial thrust bearinghaving a radius substantially equal to the radius of the circle of thecylinder axes.

14. A wobble plate mechanism comprising a stationary cylinder blockhaving a plurality of parallel cylinders arranged in a circle, pistonsin the cylinders, a rotary shaft parallel to said cylinders and coaxialwith said circle, an annular wobble plate journaled on said shaft on anaxis inclined to the shaft axis, and means operatively connecting thepistons to the wobble plate at points fixed circumferentially on'thewobble plate, the journal between the wobble plate and the shaft being acombined radial and axial thrust tially thereon, means "for bearinghaving a radius such that the portion of the bearing which is locatedclosest to the'shaft axis at any instant is spaced from the shaft axisby a distance substantially equal to theradius of the circle of thecylinder axes.

15. A wobble plate mechanism comprising a stationary cylinder blockhaving a pluralityof parallel cylinders arranged in a circle, pistons'inthe cylinders, a rotary shaft parallel to said, cylinders and coaxialwith said circle, a generally cylindrical flange fixed to the shaft onan axis inclined to and intersecting the shaft axis and'projectingtoward the point of intersection of said axes, a wobble plate journaledon said flange, means operatively connecting the pistons to said wobbleplate at points fixed circumferen-tially thereon, means for absorbingthe torque reaction on the wobble plate and restraining its movementcomprising a pair-of universal joints connected together and connectedrespectively to the wobble plate and a stationary part of the mechanism,the centers of said joints being located respe'c tively on the axis ofthe wobble plate and the axis of the shaft and being on opposite sidesof and at equal distances from the point of'intersection of a said axes,and the jointwhich is connected to the wobble plate being positionedwithin said flange.

16. A Wobble plate mechanism comprising a stationary cylinder blockhaving a plurality of parallel cylinders arrangedin a circle, pistons inthe cylinders, a rotary shaft parallel to said cyl inders andcoaxialwith said circle, a generally cylindrical flange fixed to theshaft on an axis inclined to and intersecting the shaft axis andprojecting toward the point of intersection of said axes and toward thecylinder block, said shaft having supporting bearings on opposite sidesof said flange, a wobble plate journaled on said flange. meansoperativelyconnecting the pistons to said wobble plate at points fixedcircumferenabsorbing the torque reaction on the wobble plate andrestraining its movement comprising a pair of universal joints connectedtogether and connected respectively to the Wobbleplate and to thecylinder block, the centers of said joints being locatedrespectively onthe axis'of the wobble plate and the axis of I the shaft and being onopposite sides of andat equal distances from the point of intersectionof said axes, the'joint which is connected to the wobble platebeingpositioned within said flange, each of said joints havingtrunnionbearings connected together by a ring surrounding said shaft,and the means connecting said joints being in the form of a ringsurrounding said shaft.

17. A wobble plate mechanism comprising a 1 stationary cylinder blockhaving a plurality of parallel cylinders arranged in a circle, pistonsin the cylinders, a rotary shaft parallel to said cylinders and coaxialwith said circle, a generally cylindrical flange fixed to the shaft onan axis inclined to and intersecting the shaft axis and projectingtoward the point of intersection of said axes and toward the cylinderblock, said shaft having supporting bearings on opposite sides of saidflange, a wobble plate journaled on said flange, means operativelyconnecting the pistons to said wobble plate at points fixedcircumferentially thereon, means for absorbing the torque reaction onthe wobble plate and restraining its movement comprising a pair ofuniversal joints connected together and connected respectively to thewobble plate and to the cylinder block, the centers of said joints beinglocated respectively on the axis of the wobble plate and the stationarycylinder block having a plurality of parallel cylinders arranged inacircle, pistons in the cylinders, a rotary shaft parallel to saidcylinders and coaxial with said 'circle,' an annular wobbleplatejournaledon said shaft on anaxis inclined to the shaft axis, meansoperatlvely connecting the pistons to the wobble plate at points fixedcircumterentiallyon the wobble plate,

ammo

mg a pair oi. aligned trunnion bearings, means pivotally connecting saidtrunnion bearings oi the second joint to the wobble plate on an axisperpendicular to the axis of said second pair of trunnion bearings, eachor said trunnion bearings being self-aligning to accommodate deflectionsunder load, a ring member for each joint surrounding the shaft andconnecting the trunnion bearings ofits joint, the centers of said jointsbeing located respectively on the axis of the shaft and the axis of thewobble plate on opposite sides of and at equal distances from theintersection oi? said axes, and means surrounding said shaft andconnecting said pairs of trunnion bearings for maintaining them parallelto each other, and

bearings for said shaft on opposite sides of said means forabsorbingthe'torque reaction-on the wobble plate and restraining itsmovement comprising a universal joint having a member provided with apair of alignedtrunnion bearings, means pivotally connecting saidtrunnion bearings to a stationary portionof themechanism on an axisperpendicular to the axis of said aligned trunnion 1 bearings, a jseconduniversal joint havingapair'oi' aligned trunnion bearings,

means pivotally connecting said trunnion bearings of the second joint tothe wobble plate on an axis perpendicular to. the axis oi'said secondpair of trunnion'bearings, each of said trunnion bearings beingself-aligning to accommodate deflections under load, the centers of saidjoints being located respectively on the axis of the shaft and the axisof the wobble plate on opposite sides or and at equal distances from theintersection of said axes, and means connecting said pairs of trunnionbearings tor maintaining them parallel to each other, i

19. A wobble plate .mechanism comprising a stationary cylinder blockhaving'a plurality of parallel cylinders arranged in a circle, pistonsinthe cylinders, a rotary shaft parallel to said cylinders andcoaxialwith said circle, .an annular wobble plate Journaled on saidshaft onan axis inclined ,to the shaft axis, means operativelyconnecting the pistons to the wobble plate at points fixedcircumferentially on the wobble plate; means for absorbing the torquereaction on the wobble plate and restraining its movement comprising auniversal joint having a member provided with a pair of aligned trunnionbearings, means plvotally connecting said trunnion bearuniversal joints.

20. A wobble plate mechanism comprising a stationary cylinder blockhaving a plurality of parallel cylinders arranged in a circle, pistonsin the cylinders, a rotary shaft parallel to said cylin- 4 ders andcoaxial with said circle, an annular wobble plate journaled on'saidshaft on an axis inclined to the shaft axis, means operativelyconnecting the pistons to the wobble plate at points fixedcircumferentially "on the wobble plate, and meansfor absorbing thetorque reaction on the wobble plate and restraining its movementcomprising a four trunnion universal joint connected to 'a stationaryportion oi! the mechanism with the center of the joint on the axis 0!said shaft, a second four trunnion universal joint connected to thewobble plate with its center on the axis of the wobble plate, each ofsaid trunnion bearings being self-aligning to accommodate deflectionsunder load, the centers of said joints being located on opposite sidesor and at equal distances from the point of intersection of said axes,and a member operatively connecting one pair 01" aligned trunnionbearings of one of said joints with a parallel pair of aligned trunnionbearings of the other 110111122:

FRANK C. HOWARD.

REFERENCES orrEn 5 die of, this patent:

lugs to a stationary portion of the mechanism on an axis perpendicularto the axis of said aligned trunnion bearings, a second universaljointhav- UNITED s'rnTEs PATENTS 1,781,131 Shaft NOV. 11, 1930

